Finally
getting back to this topic… I created a worksheet for one of my customers that detailed
the configuration of Kerberos & delegation. There are really two tracks that need
to be followed: 1) Confirm that authentication works on the client, front-end server,
and back-end servers, and 2) Confirm that Active Directory, trust relationships and
DNS are all configured correctly.
This list certainly isn’t inclusive of all delegation scenarios but it should be helpful.

Jim
DeVries’ Infrastructure and Technology Blog : Kerberos / Delegation Worksheet.